1. Field of the Invention
The present invention relates to electronic apparatus having an operation panel as a man-machine interface, which includes communication apparatuses such as a facsimile apparatus, and information processing apparatuses. More particularly, the invention relates to detection and recovery of malfunctions in the operation panel.
2. Description of the Related Art
Conventionally, a communication apparatus and an information processing apparatus generally have an operation panel as a man-machine interface with a user. The operation panel is a portion where the user directly touches or comes in closest proximity. Static electricity often collects on the user due to friction with the clothes he is wearing. In cases where the static electricity collects on the user, the static electricity on the user is discharged to the operation panel, and a high voltage developed by the discharge often causes a malfunction in the operation panel. Hence, the operation panel is a portion that needs the antistatic measure most. For this reason, measures have been taken for the operation panel, according to which an additional conducting material is employed to reduce static influence on a circuit portion, the structure is refined, etc. The placement of the circuit component or the like is also concerned in many cases to reduce the static influence.
For example, Japanese Unexamined Patent Publication JP-A 9-309245 (1997) proposes an idea of reducing static-induced malfunctions in the operation panel of a recording apparatus by a structure in a mechanism portion of the operation panel without employing any additional antistatic component. Such a static preventive measure by means of mechanism is one of the important antistatic measures. Japanese Unexamined Patent Publication JP-A 8-263020 (1996) discloses a prior art of a liquid crystal driving method such that a display content on the liquid crystal panel will not be changed even when a power-on-reset function is triggered by influence of noises or the like.
Generally, electronic apparatus that is furnished with a microcomputer and runs a program has a possibility of a noise-induced malfunction, causing deviation from normal operations according to the original program. Japanese Unexamined Patent Publication JP-A 6-12335 (1994) proposes an idea to divide a RAM area of a facsimile apparatus into a plurality of memory areas, and store various parameters of the same contents in each memory area. Here, a CPU calculates and stores a checksum for each block in the memory areas. The CPU calculates the checksum periodically, and compares the latest checksum with the stored checksum, and when there is a discrepancy, the CPU calculates the checksum of another memory area and uses various parameters in the correct memory area, whereby error recovery is achieved. Japanese Unexamined Patent Publication JP-A 7-168740 (1995) discloses a watchdog method adapted to a videocassette recorder enclosing two interconnected microcomputers, according to which, when one of the microcomputers is in an error state, the other microcomputer detects the error and automatically resets the microcomputer in the error state. Here, upon receipt of a request command of watchdog data from the other microcomputer, the recipient microcomputer transmits the data in responding to the command, so that an error is detected by checking whether the data is correct or not.
The operation panel serving as a man-machine interface in a communication apparatus, an information processing apparatus or the like is generally isolated from the main circuit portion in the main body, and often arranged in the easiest-to-use design or placed in the easiest-to-use location for the user. In this case, as a typical embodiment, the operation panel is placed so as to operate independently from the main circuit portion, and connected to the main circuit portion via a cable or a wire. However, with portable electronic apparatus that should meet the need of downsizing, there may be a case where the operation panel is formed on the surface of the flat housing, and the main circuit portion is placed in the interior of the housing. In any case, the operation panel serving as the man-machine interface is most susceptible to static electricity. In particular, when an electronic circuit for driving a display section and an electronic circuit for generating an electrical signal in response to an input operation at an input operating section are provided to the interior of the operation panel, the electronic circuit portions are susceptible to static electricity, and a static-induced malfunction of the electronic circuits in the operation panel results in a serious problem.
The method of reducing the static influence by means of mechanism as disclosed in JP-A 9-309245 supra is certainly applicable. However, the influence of static electricity collected on the user varies in static voltage, applied portion, etc., and it is quite difficult to prevent the influence completely. A static-induced malfunction may mean, depending on an applied portion or strength of the static electricity, a bit error in a bit map memory that retains data for a display apparatus, or other types of malfunction, such as a runway of a program in a control portion that controls the operation panel, the latch-up in an LSI, etc. Therefore, it is necessary to take adequate recovery measures or countermeasures including prevention of a fatal damage for each occasion. The method described in JP-A 8-263020 supra is intended to prevent a malfunction caused by the power-on-reset function triggered when a noise signal is mixed into a power line, and therefore, this method cannot perform an adequate recovery process to restore the display content at the occurrence of a noise-induced malfunction such that changes the display content.
It is therefore an object of the invention to provide electronic apparatus having an operation panel and capable of performing adequate malfunction recovery at the occurrence of a static-induced malfunction in the operation panel.
The invention provides electronic apparatus having an operation panel which is provided with a display section and an input operating section and serves as a man-machine interface, comprising:
condition setting means for presetting a condition, under which an operation of detecting a malfunction in the operation panel is repeated;
information storing means for storing information transmitted as a display content for the display section of the operation panel;
content reading out means for reading out the display content displayed on the display section of the operation panel each time the condition set in the condition setting means is satisfied;
malfunction judging means for comparing the display content read out by the content reading out means and displayed on the display section with the information stored in the information storing means, and based on a comparison result, judging whether there is a malfunction in the operation panel; and
malfunction recovering means for, when the malfunction judging means determines that there is a malfunction in the operation panel, effecting a predetermined control for malfunction recovery.
According to the invention, the electronic apparatus has the operation panel provided with the display section and input operating section and serving as a man-machine interface. The electronic apparatus having the operation panel includes the condition setting means, information storing means, content reading out means, malfunction judging means, and malfunction recovering means. The condition setting means presets a condition, under which an operation of detecting a malfunction in the operation panel is repeated. The information storing means stores information transmitted as a display content for the display section of the operation panel. The content reading out means reads out the display content displayed on the display section of the operation panel each time the condition set in the condition setting means is satisfied. The malfunction judging means compares the display content read out by the content reading out means and displayed on the display section with the information stored in the information storing means, and judges whether there is a malfunction in the operation panel, based on a comparison result. When the malfunction judging means determined that there is a malfunction in the operation panel, the malfunction recovering means effects the predetermined control for malfunction recovery. Because the detection of malfunctions in the operation panel is carried out repetitively, and the predetermined control for malfunction recovery is effected upon determining that there is a malfunction, a static-induced malfunction or the like can be recovered adequately. When no malfunction is detected, the malfunction recovery process is not executed. Hence, it is possible to eliminate an inconvenience such that the display section flickers due to the recovery process executed regardless of the absence of a malfunction.
In the invention, it is preferable that the malfunction judging means analyzes input information in the input operating section of the operation panel, and based on a result of analysis, judges whether there is a malfunction in the operation panel.
According to the invention, whether there is a malfunction or not is judged also with respect to input information to the input operating section that is susceptible to static electricity collected on the user or the like, and when the malfunction judging means determines that there is a malfunction, an adequate malfunction recovery process can be executed.
In the invention, it is preferable that the malfunction recovering means carries out a recovery process comprising retransmission of the information stored in the information storing means to the display section of the operation panel as a control for malfunction recovery, and when the malfunction is not recovered by the recovery process, supply of power to at least the operation panel is cut off.
According to the invention, the malfunction recovering means performs a recovery process comprising retransmission of the information stored in the information storing means to the display section of the operation panel as a control of malfunction recovery. When the malfunction is not recovered by the recovery process, the malfunction recovering means cuts off supply of power to at least the operation panel. Thus, for a malfunction such that can be recovered by merely retransmitting the display content, the recovery process is executed with the other components being less influenced, and for a malfunction such that cannot be recovered by such a recovery process, the malfunction is determined as being a critical malfunction or a failure, and supply of power to at least the operation panel is cut off, thereby making it possible to prevent fatal damage or the like.